Solar energy utilization system

Abstract

To provide a solar energy utilization system capable of efficiently utilizing solar energy by a synergistic effect of a solar cell panel and a solar water heater.SOLUTION: The solar energy utilization system includes a perovskite solar cell part 12 for converting light energy of sunlight into electric energy, and a solar heat water heater heat collecting plate 14 disposed below the perovskite solar cell part 12 and collecting heat obtained from the sunlight passing through the perovskite solar cell part 12, and includes a case body 20 for storing the perovskite solar cell part 12 and the solar heat water heater heat collecting plate 14, a tempered glass part 16 disposed in the case body 20 and for placing the perovskite solar cell part 12 thereon, and a flow passage part 18 provided in the case body 20 and for allowing a fluid to flow therethrough for exchanging heat collected by the solar heat water heater heat collecting plate 14.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a solar energy utilization system. [Background technology]

[0002] In the past, as a technology using solar energy, a solar water heater and a photovoltaic power generation system have been installed separately. For example, Patent Document 1, which is a technology related to the present invention, describes a water heater body having several heat exchange tubes and a hot water manifold to which these heat exchange tubes are connected, a frame fitted around the water heater body, a first reflecting plate and a second reflecting plate symmetrically provided on both sides of the frame, two heat insulating layers respectively provided on the backs of the first reflecting plate and the second reflecting plate, two protective covers respectively provided on the two heat insulating layers, two rotary drivers respectively provided on both sides of the frame, connecting the bottom ends of the first reflecting plate and the second reflecting plate, and driving the first reflecting plate and the second reflecting plate to rotate, and a control system which electrically connects the two rotary drivers and controls the two rotary drivers according to the direction of sunlight irradiation to rotate the first reflecting plate and the second reflecting plate. A synergistic effect solar water heater is disclosed, which includes a solar tracking controller that drives and rotates the reflector to form a light-receiving reflecting surface angle, reflects the sunlight onto these heat exchange tubes, flows the internal water source through these heat exchange tubes to exchange heat, becomes hot water, and then collects it in the hot water manifold, and in the absence of sunlight, controls the two rotary drivers to simultaneously drive and rotate the first reflector and the second reflector, stacking and covering them on the water heater main body, thereby serving as a laminated protective cover for the water heater main body.

[0003] Furthermore, Patent Document 2 discloses a solar panel-floor integrated hot water supply structure in which the floor of a normal solar water heater is covered with solar panels, and the upper water tank is made of a transparent material such as glass, so that the water in the tank is heated by the black heat absorption effect of the solar panel, while also generating electricity, which is its original function. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-57052 [Patent Document 2] Japanese Patent Application Laid-Open No. 2000-64946 Summary of the Invention [Problem to be solved by the invention]

[0005] The above Patent Documents 1 and 2 disclose a configuration in which a solar water heater and a solar cell are used in combination, but do not describe a use in which a synergistic effect is produced by overlapping the solar cell and the solar water heater.

[0006] An object of the present invention is to provide a solar energy utilization system that enables efficient utilization of solar energy through the synergistic effect of a solar cell and a solar water heater. [Means for solving the problem]

[0007] The solar energy utilization system according to the present invention is characterized by comprising: a perovskite solar cell unit that converts the light energy of sunlight into electrical energy; and a heat collection plate for a solar water heater that is disposed below the perovskite solar cell unit and collects heat obtained from the sunlight that has passed through the perovskite solar cell unit.

[0008] The solar energy utilization system according to the present invention is characterized by comprising: a case body for accommodating the perovskite solar cell unit and the solar water heater heat collection plate; a tempered glass part provided within the case body and for placing the perovskite solar cell unit thereon; and a flow passage part provided within the case body and in contact with the solar water heater heat collection plate installed via an air layer provided between the tempered glass part and the case body, for flowing a fluid to exchange heat collected by the solar water heater heat collection plate.

[0009] In the solar energy utilization system according to the present invention, it is preferable that the flow passage portion has a mesh-like flow passage that is stretched over the entire area of ​​the solar heat collecting plate.

[0010] In the solar energy utilization system according to the present invention, the fluid is preferably oil. [Effects of the Invention]

[0011] According to the present invention, solar energy can be utilized efficiently by the synergistic effect of the solar cell and the solar water heater. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing a solar energy utilization system according to an embodiment of the present invention; [Figure 2] 1 is a diagram showing a case body that houses a perovskite solar cell unit and a heat collection plate for a solar water heater in a solar energy utilization system according to an embodiment of the present invention. FIG. [Figure 3] FIG. 1 is a diagram for explaining the advantages of using a perovskite solar cell unit in a solar energy utilization system according to an embodiment of the present invention. [Figure 4] FIG. 1 is a diagram for explaining the advantages of using a perovskite solar cell unit in a solar energy utilization system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following, similar elements in all drawings will be designated by the same reference numerals, and duplicate explanations will be omitted. Furthermore, in the description below, previously described reference numerals will be used as necessary.

[0014] Fig. 1 is a diagram showing a solar energy utilization system 10 according to an embodiment of the present invention. Fig. 2 is a diagram showing a case body 20 that houses a perovskite solar cell unit 12 and a solar water heater heat collection plate 14 of the solar energy utilization system 10 according to an embodiment of the present invention.

[0015] 3 and 4 are diagrams for explaining the advantages of using the perovskite solar cell section 12 in the solar energy utilization system 10 according to the embodiment of the present invention.

[0016] The solar energy utilization system 10 is a system that utilizes solar energy to obtain thermal energy and electrical energy. The solar energy utilization system 10 includes a perovskite solar cell unit 12 that converts solar light energy into electrical energy, a solar water heater heat collection plate 14 that collects solar heat, a tempered glass unit 16, a flow passage unit 18, a case body 20, a heat pump 22, a heat-retaining hot water tank 24, a junction box 26, a power conditioner 28, a distribution board 30, and a storage battery 32.

[0017] In the perovskite solar cell unit 12, perovskite crystals on a substrate absorb light and generate electricity. The perovskite solar cell unit 12 has a structure in which thin films are layered, and is made by applying materials to the substrate in a paint-like manner, so low-cost substrates such as films can be used. Because the substrate is a film, it has the advantage of being light and flexible.

[0018] The perovskite solar cell section 12 has a perovskite layer in the center that absorbs light and generates positive and negative charges. The perovskite layer is sandwiched between a hole transport layer that extracts positive charges and an electron transport layer that extracts negative charges, and is further sandwiched between two electrodes.

[0019] The perovskite solar cell unit 12 can be bent or folded, allowing it to be adapted to a variety of shapes, and its manufacturing costs are expected to be about 1 / 3 to 1 / 5 of those of silicon-type solar cells.It also has high energy conversion efficiency and can generate electricity even under weak light.

[0020] As shown in Figure 3(b), the perovskite solar cell unit 12 absorbs sunlight in the visible light range (380 to 780 nm) and absorbs almost no sunlight in the infrared range. Conventional silicon solar panels absorb sunlight in the infrared range, making it difficult to absorb it as solar heat, but the perovskite solar cell unit 12 allows sunlight in the infrared range to pass through.

[0021] The perovskite solar cell unit 12 efficiently absorbs sunlight in the visible light range (380 to 780 nm), making it possible to generate electricity even on cloudy or rainy days. Figure 4 shows a comparison of power generation in Tokyo under various weather conditions over one day using perovskite solar cells and conventional silicon solar cells.

[0022] On a normal sunny day as shown in Figure 4(a), conventional silicon solar power generation generates more electricity, but on a cloudy or rainy day as shown in Figure 4(b), the perovskite solar cell unit 12 generates about three times more electricity than conventional silicon solar power generation. Comparing the weather over the year, there is data that shows that the total amount of electricity generated throughout the year does not change much, as sunny days and non-sunny days (cloudy and rainy days) account for half the total.

[0023] The solar water heater heat collection plate 14 is disposed below the perovskite solar cell section 12 and has the function of collecting heat obtained from sunlight that has passed through the perovskite solar cell section 12.

[0024] The solar water heater heat collection plate 14 is preferably made of a black aluminum plate. Aluminum has a specific heat (J / kg°C) of 900, a thermal conductivity (W / mK) of 204, a melting point (°C) of 660.2, and a specific gravity (g) of 2.70.

[0025] For comparison, iron has a specific heat (J / kg°C) of 444, a thermal conductivity (W / mK) of 80, a melting point (°C) of 1538, and a specific gravity (g) of 7.87, while zinc has a specific heat (J / kg°C) of 383, a thermal conductivity (W / mK) of 113, a melting point (°C) of 419.46, and a specific gravity (g) of 7.14.

[0026] Copper has a specific heat (J / kg℃) of 419, a thermal conductivity (W / mK) of 372, a melting point (℃) of 1083, and a specific gravity (g) of 8.93, while magnesium has a specific heat (J / kg℃) of 1013, a thermal conductivity (W / mK) of 54, a melting point (℃) of 650, and a specific gravity (g) of 1.74.

[0027] Stainless steel has a specific heat (J / kg°C) of 460, a thermal conductivity (W / mK) of 16, a melting point (°C) of 1400, and a specific gravity (g) of 7.70, while water (20°C) has a specific heat (J / kg°C) of 4182, a thermal conductivity (W / mK) of 0.602, a melting point (°C) of 0, and a specific gravity (g) of 1.0. Considering these factors, aluminum is ideal for use as a heat collector plate, as it has high thermal conductivity, is light in weight, and is low in cost.

[0028] The tempered glass portion 16 is glass on which the perovskite solar cell portion 12 is placed. The tempered glass portion 16 is made by heat-treating regular glass (float glass) and then rapidly cooling it, and has approximately 3.5 to 4 times the wind pressure resistance of float glass. It looks exactly the same as float glass and is indistinguishable from it. Another characteristic of tempered glass is that while regular glass breaks sharply like a blade, the tempered glass portion 16 shatters into pieces.

[0029] The flow passage portion 18 is in contact with the solar water heater heat collection plate 14, which is installed via the air layer 13 provided between the tempered glass portion 16, and is a flow path for flowing a fluid to exchange the heat collected by the solar water heater heat collection plate 14. The air layer 13 is provided to prevent the heat collected by the solar water heater heat collection plate 14 from being taken away by the tempered glass portion 16.

[0030] Industrial oil flows through the flow passage 18. The industrial oil has a specific heat (J / kg°C) of 1796, a thermal conductivity (W / mK) of 0.148, and an expansion coefficient (×10 -3 / ℃) is 0.70 and the specific gravity (g) is 0.8 to 0.9.

[0031] The specific heat, thermal conductivity, expansion coefficient, and specific gravity of water vary depending on the temperature: 0°C, 20°C, 80°C, and 100°C. At 0°C, the specific heat (J / kg°C) is 4217, the thermal conductivity (W / mK) is 0.569, and the expansion coefficient (×10 -3 / ℃) is -0.06, and the specific gravity (g) is 1.0. The specific heat (J / kg℃) at 20℃ is 4182, the thermal conductivity (W / mK) is 0.602, and the coefficient of expansion (×10 -3 / ℃) is 0.65 and the specific gravity (g) is 1.0.

[0032] The specific heat (J / kg°C) at 80°C is 4196, the thermal conductivity (W / mK) is 0.672, and the expansion coefficient (×10 -3 / ℃) is 0.65, and the specific gravity (g) is 1.0. The specific heat (J / kg℃) at 100℃ is 4215, the thermal conductivity (W / mK) is 0.682, and the coefficient of expansion (×10 -3 / ℃) is 0.78 and its specific gravity (g) is 1.0. Thus, the specific heat of oil is less than half that of water, so it absorbs heat faster and is lighter in weight than water.

[0033] As shown in Figure 2, the flow passage section 18 is provided with large pipes 18a that function as a main artery in a plan view and extend from side to side to cover almost the entire area of ​​the solar heat collection plate 14, medium pipes 18b that extend vertically and horizontally to form a large mesh lattice, and small pipes 18c that extend vertically and horizontally to form a small mesh lattice.

[0034] The flow passage portion 18 may be made of any material having a suitable strength, such as a mixture of magnesium, zinc, and aluminum, but may also be made of other materials.

[0035] The case body 20 is a case that houses the perovskite solar cell section 12, the air layer 13, the solar water heater heat collection plate 14, the tempered glass section 16, and the flow passage section 18.

[0036] The case body 20 has a tray-like shape with an open top. As shown in the cross-sectional view of Figure 2(b), the tempered glass part 16 and the solar water heater heat collection plate 14 are directly fixed to the case body 20. The perovskite solar cell part 12 is placed and attached to the front surface (upper surface) of the tempered glass part 16, and the flow passage part 18 is attached to the back surface (lower surface) of the solar water heater heat collection plate 14 so as to come into contact with it.

[0037] The case body 20 is preferably made of a material having a suitable strength, and can be made of, for example, a composite plate of aluminum and polyethylene resin, but of course it may be made of other materials.

[0038] The heat pump 22 includes a compressor that compresses the refrigerant and turns it into a high-temperature, high-pressure gas; a condenser where the compressed refrigerant releases heat and turns into a liquid; an expansion valve that rapidly expands the refrigerant to reduce its temperature and pressure; and an evaporator where the refrigerant absorbs ambient heat and turns back into a gas.

[0039] The heat pump 22 can efficiently transfer heat by repeating the following steps: evaporation process in which the refrigerant absorbs ambient heat in the evaporator and changes from liquid to gas; compression process in which the gaseous refrigerant is compressed in the compressor to become a high-temperature, high-pressure gas; condensation process in which the high-temperature, high-pressure gas releases heat in the condenser and changes back to liquid; and expansion process in which the liquid refrigerant passes through an expansion valve and rapidly expands to a low-temperature, low-pressure state.

[0040] The insulated hot water tank 24 is a tank for storing hot water heated by the heat pump 22. The insulated hot water tank 24 can be made of stainless steel (e.g., SUS444) or resin-lined steel plate, which makes it corrosion-resistant and allows the supply of clean hot water.

[0041] Here, a configuration including the solar water heater heat collection plate 14, the flow passage portion 18, the heat pump 22, and the heat-retaining hot water tank 22 is called a solar water heater 6.

[0042] The junction box 26 is one of the important components of the solar power generation system, and is a device for connecting the perovskite solar cell unit 12 and the power conditioner 28. The junction box 26 collects the DC power generated by the perovskite solar cell unit 12 and sends it to the power conditioner 28. This converts the DC power into AC power.

[0043] The junction box 26 has the function of adjusting voltage variations when combining the power from multiple perovskite solar cell units 12. The junction box 26 incorporates safety devices such as switches and lightning protection elements, and has the function of controlling the flow of electricity and protecting equipment from lightning strikes.

[0044] The power conditioner 28 automatically finds the combination of voltage and current that maximizes the power generation output of the perovskite solar cell unit 12, supporting efficient power generation. The power conditioner 28 has the function of transmitting generated power at an appropriate voltage when selling it to the power company. This prevents the backflow of power and ensures a stable power supply. The power conditioner 28 also has the function of cutting off output in the event of a power outage or abnormality, preventing accidents. This ensures the safe operation of the solar power generation system.

[0045] The distribution board 30 has the function of distributing electricity generated by the perovskite solar cell unit 12 and electricity supplied by the power company to various devices and rooms in the home. The distribution board 30 is equipped with a breaker that detects leakage and overcurrent and cuts off the electricity, preventing fires and electric shock accidents. The distribution board 30 also has the function of reversing the flow of electricity when excess electricity from the perovskite solar cell unit 12 is sold to the power company. This allows for efficient use of the generated electricity.

[0046] The storage battery 32 stores the electricity generated by the perovskite solar cell unit 12, making it possible to use the electricity even during times when solar power generation is not possible, such as at night or on cloudy days. The storage battery 32 also plays a role in stabilizing the power supply, making it possible to provide a stable power supply even in areas where the power supply is unstable.

[0047] The storage battery 32 stores the electricity generated by the perovskite solar cell unit 12, thereby reducing the amount of electricity purchased from the power company and saving on electricity bills. The storage battery 32 can supply power for a certain period of time by using the stored electricity during a power outage.

[0048] The storage battery 32 may be, for example, a lithium ion secondary battery, but may of course be any other secondary battery, such as a nickel-metal hydride battery.

[0049] Here, a configuration including the perovskite solar cell unit 12, the tempered glass unit 16, the junction box 26, the power conditioner 28, the distribution board 30, and the storage battery 32 is referred to as a solar power generation system 8.

[0050] Next, we will explain the operation of the solar energy utilization system 10 configured as described above. First, we will compare silicon solar power generation with the perovskite solar cell unit 12. As shown in Figure 3(b), the perovskite solar cell unit 12 efficiently absorbs sunlight in the visible light range (380 to 780 nm), making it possible to generate power even on cloudy or rainy days.

[0051] Figure 4 compares the power generation in Tokyo in various weather conditions for the perovskite solar cell unit 12 and conventional silicon solar power generation. As mentioned above, on normal sunny days, conventional silicon solar power generation generates more power, but on cloudy or rainy days, the perovskite solar cell unit 12 generates about three times more power than the conventional type. Comparing the weather over the course of a year, sunny days and non-sunny days (cloudy or rainy days) account for about half the total, so the total power generation throughout the year does not change much.

[0052] Figure 3 shows the relationship between the wavelength and spectrum of light absorbed by conventional silicon-based photovoltaic power generation. As mentioned above, as shown in Figures 3(a) and 3(c), silicon-based photovoltaic power generation absorbs not only visible light in the 380 to 780 nm range but also infrared light.

[0053] As described above, the perovskite solar cell unit 12 absorbs sunlight in the visible light range (380 to 780 nm) and absorbs almost no sunlight in the infrared range. Conventional silicon solar cell power generation absorbs sunlight in the infrared range as well, making it difficult to absorb the sunlight as solar heat.

[0054] In contrast, in the solar energy utilization system 10 according to an embodiment of the present invention, the perovskite solar cell unit 12 allows sunlight energy to pass through in the infrared region, so the solar water heater heat collection plate 14 can efficiently absorb heat energy, making it possible to absorb approximately six times the amount of heat compared to silicon-type solar power generation.

[0055] Generally, the solar water heater 6 supplies heat as energy, is used for hot water supply and heating, has an energy efficiency of 40 to 60%, and is applicable to buildings with a high demand for hot water such as hospitals, hotels, welfare facilities, and schools, and has a supply energy per unit area of ​​600 kW / m 2 In contrast, the solar power generation system 8 supplies electricity, which is used for electrical appliances and for selling electricity to electric power companies, has an energy efficiency of 7 to 18%, can be installed in a variety of buildings, and supplies 130 kW / m of energy per unit area. 2 is.

[0056] Thus, the energy efficiency of the solar water heater 6 is better than that of the solar power generation system 8, but conventionally, vacuum tubes were necessary to prevent the heat obtained from sunlight from being dissipated. However, vacuum tubes are expensive and have the problem of being fragile and easily broken. Furthermore, because conventional solar water heaters use water, they have durability issues and are excessively heavy (200-400 kg). Furthermore, because they use water, even if antifreeze is added, the water freezes in cold regions in winter, which makes installation in those regions unfeasible.

[0057] The solar energy utilization system 10 according to the embodiment of the present invention has a remarkable effect in addressing these issues. Specifically, by replacing water with oil, problems such as rust are eliminated, oil does not freeze (approximately -60°C), so it can be used in cold regions, and because only a small amount of oil is circulated, the problem of excessive weight is also solved (weight: approximately 20 to 50 kg).

[0058] In the solar energy utilization system 10, the circulating oil flows through the large pipes 18a, then through the medium pipes 18b that form a large mesh, and also through the small pipes 18c that form a fine mesh, so that it spreads over the area on the back side of the solar hot water collector plate 14, as shown in Figure 2. As a result, since the oil circulates within the equipment, there are almost no problems with heat dissipation, and the heat pump 22 has good thermal efficiency even at low temperatures, making it possible to maintain a constant high temperature of hot water in the insulated hot water tank 24.

[0059] In this way, solar water heaters using oil are highly efficient in using energy from sunlight. They achieve a high efficiency of about 40-60% in heat conversion. In the case of water, the pipes deteriorate due to rust and limescale, so the durability is about 10 years, but oil is resistant to corrosion such as rust and has a durability of about 20-30 years.

[0060] In cold regions, water freezes (to about 0°C), but oil (to about -60°C) has little risk of freezing. The specific heat of oil is about half that of water, so it absorbs heat faster and circulates efficiently with heat pump 22 even at low temperatures.

[0061] Water expands at high temperatures (approximately 100°C), but oil (approximately 400°C) does not expand due to heat, so there is less risk of accidents.Even a small amount of oil circulates through the solar hot water heater 6 with efficient heat exchange, so the total weight of the equipment when installed on a roof is lighter.

[0062] As described above, according to the solar energy utilization system 10, the perovskite solar cell unit 12 can generate more power than conventional silicon solar power generation using sunlight in the visible light range (380 to 780 nm), and since it can pass infrared light, heat can be obtained at the solar hot water heater heat collection plate 14, which has the advantage of being able to absorb approximately six times the amount of heat compared to conventional silicon solar power generation.

[0063] In addition, the solar water heater 6 heats water absorbed by the heat pump 22 and sends it to the insulated hot water tank 24 where it is stored. This stored hot water is used for hot water supply, hot water floor heating, boiling water for the bath, etc. Furthermore, the electricity generated in the perovskite solar cell unit 12 is transmitted to the power conditioner 28 and distribution board 30, and then sent to household electrical appliances and a storage battery 32.

[0064] The components of the solar energy utilization system 10 are merely examples and can be changed as appropriate. For example, the solar water heater 6 has been described as using the heat pump 22, but a normal heat exchanger may also be used. [Explanation of symbols]

[0065] 6 Solar water heater, 8 Photovoltaic power generation system, 10 Solar energy utilization system, 12 Perovskite solar cell part, 13 Air layer, 14 Heat collection plate for solar water heater, 16 Tempered glass part, 18 Flow passage part, 18a Large pipe, 18b Medium pipe, 18c Small pipe, 20 Case body, 22 Heat pump, 24 Insulated hot water tank, 26 Junction box, 28 Power conditioner, 30 Distribution board, 32 Storage battery.

Claims

1. a perovskite solar cell unit that converts light energy from sunlight into electrical energy; a solar water heater heat collection plate disposed below the perovskite solar cell unit and configured to collect heat obtained from the sunlight that has passed through the perovskite solar cell unit; A solar energy utilization system comprising:

2. 2. The solar energy utilization system according to claim 1, a case body for accommodating the perovskite solar cell unit and the solar water heater heat collection plate; a tempered glass portion provided in the case body and on which the perovskite solar cell portion is placed; a flow passage portion provided within the case body, in contact with the heat collection plate for the solar water heater, which is installed with an air gap between the case body and the tempered glass portion, and through which a fluid flows to exchange heat collected by the heat collection plate for the solar water heater; A solar energy utilization system comprising:

3. 3. The solar energy utilization system according to claim 2, The solar energy utilization system is characterized in that the flow passage portion has a mesh-like flow path that is spread throughout the entire area of ​​the solar heat collecting plate.

4. 4. The solar energy utilization system according to claim 2 or 3, A solar energy utilization system, characterized in that the fluid is oil.

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